Since purchasing my 2CV last August I've found tons of surprises and mysteries on this car.

I have no idea how I overlooked this considering I've spent hours over the engine multiple times fiddling with the crossbox.

The other day I was installing a battery cable and found something shocking.

Look at the right brake line fitting on this caliper:



I noticed some oil on top of this particular caliper but assumed it was gearbox oil leaking from the seal. So I sprayed some brake cleaner on the caliper. Then all of a sudden the leak stopped.

What's even more surprising is the left brake line appears to be the one that was actually leaking.

I had to order some of this special green Citroen brake fluid so after I topped it off eventually I noticed the reservoir level had dropped a bit. So instead of gearbox oil, it was brake fluid.

So as I was installing the battery cable I looked down and noticed the brake line fitting was not even screwed into the caliper! I actually think it was screwed in a couple of threads when I first got the car but must have vibrated out. Despite having to use a little bit of effort to screw it back on.

I checked the others and some were screwed in but just hand tight. So I snugged all three up. I did not think the check the bleeder screw but will.

How in the world could this have possibly happened? How could the last person who serviced the brakes or whatever that could have required removing the brake calipers have overlooked this? Whenever I service brakes, one of the things I always do is check for leaks.

I have no idea how why I was not loosing anymore fluid than I was. I can't believe I've been driving this car with this.

Lucky, The dual setup would have given you rear brakes.

Damn lucky you didn't need to do an emergency stop! The pressure could have blown that seal out completely.
Someone's clearly tarted this car up, I've never seen a painted gearbox before. One top casing bolt is too long for its location. If you take the leaking union out, check that there is actually a seal in there. Chances are there isn't! That should make you look at the whole car more closely.

hope they did put the right rubber bushes in for the green brake fluid. You were very lucky it didn't pop out.
Other lucky thing the green liquid doesn't corrode paint..

I was thinking all Citroens (or 2CVs anyway) with front disc brakes used the green brake fluid. It was just the older models with 4 wheel drum brakes that used DOT 3 brake fluid.

Correct me if I am wrong but I read somewhere if you couldn't find the green brake fluid you could substitute baby oil which is a lightweight mineral oil. Then to have the system flushed out whenever possible. If your braking system is loosing that much brake fluid where it has to be topped off regularly, then I'd say it's a good idea not to drive the car until the leak is fixed!

I would think in Europe you could find this green brake fluid about anywhere. Only in the United States would I have to find a substitute since I don't know of any other cars that actually use this stuff. I've never seen it at any auto part store. Just like I've never seen GL-4 gearbox oil at any auto part store.

I bought a liter of it when I ordered my cross box and some other parts so no worries.

It seems that the newer JCB diggers use the LHM too. Also some elevating hatches on trucks. Yes you are right it is in the disc brake 2cv's but the drum brake versions use the same type of brake lines but with red striped rubbers for normal dot brake fluid.

I was thinking you were saying my calipers might have DOT 3 rated piston seals in them. I did not know about the brake hoses. So if my brake hoses have red strips on them, they are not rated for LHM brake fluid?

2CVs didn't have brake hoses after the late 60's. AZL57 is talking about the seals used at the pipe joints. Both disc brake and drum brake 2CVs (from the late sixties onwards) use the same method of sealing the 3.5mm metal brake pipes, at every joint/union. The type of rubber used for the seals is different depending on whether they are for Dot3/4 fluid (drum brake cars) or LHM (disc brake cars). Dot3/4 have a red stripe or dot. LHM have a green stripe or dot. (Sometimes the seals that are supplied with a new component, don't have a colour marked on them).

That's correct! There are no front brake hoses on a 2CV!

By 'snugged', I hope you didn't overtighten them, since the torque required for these 3.5mm 'pilot & bulge' brake line joints is only 6 ft.lbs.
Overtightening the bush nut can mean that it's extremely difficult to remove the brake pipe from the component to which it's fitted, which is probably what's happened with your car.
As Derek has aready commented, the 'restorer' may well have been focussed on nonsense such as painting the gearbox casing, instead of the proper 'nuts and bolts' aspects of a restoration...